An immigration and constitutional law expert said the Trump administration's changes to federal policies are leaving many immigrants who believed they were safe from deportation in limbo.

Hanover Park police officer Radule Bojovich was arrested this week by U.S. Immigration and Customs Enforcement agents, accused of overstaying a tourist visa, despite claims from the village that he had a valid work authorization card that was recently renewed.

ICE and the Department of Homeland Security have said Bojovic, who is from Montenegro, was living in the U.S. on a tourist visa that expired March 31, 2015, and illegally overstaying his visa by more than ten years.

Hanover Park officials, however, said he was "legally authorized by the federal government to work in the United States" and that U.S. Citizenship and Immigration Services had issued him a "valid and recently renewed" work authorization card.

The village also said Bojovich passed a full background check both the Illinois State Police and FBI, and that a memo from the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives confirmed his immigration status allows him to carry a firearm while on duty.

A spokesperson for Illinois State Police said all police officers submit to their background check, which "covers criminal history, not immigration status."

Bojovic was being held at the Clay County Justice Center in Indiana on Friday after his arrest.

Northwestern Pritzker School of Law professor Paul Gowder, a constitutional law specialist who works at the intersection of immigration and constitutional law, spoke about changes to federal immigration policy under the Trump administration.

"They're trying to classify a bunch of people as removable who under the Biden administration would not have been understood as subject to removal," he said. "The Trump administration has been going in and initiating changes to a lot of the policies that are predicates for people getting work authorization. They've been going in and trying to revoke authorizations, revoke parole, revoke temporary protected status. There's still disagreement about whether many of these changes they are trying to implement are legal, and so a lot of people can kind of be in a sort of limbo."

With changes happening rapidly, Gowder had some advice to immigrants who feel they could be vulnerable now, even if they were granted some sort of protection from deportation in the past.

"It is a valid concern, and I think that people who have any reason to believe that there's any uncertainty about their status really should talk to an immigration lawyer, and make sure they have all their ducks lined up in a row," he said.

Representatives for Homeland Security, ICE, and the FBI did not respond to requests for comment.